The Hallerbos (French: Bois de Hal) is a forest with an area of 552 ha southeast of Halle (511 ha on Halle territory). The forest is largely owned by the Flemish Region and a small part by the Walloon Region and private properties. The Hallerbos is a quiet recreation area, which is highly appreciated by the population of the surrounding highly urbanized areas. It is very accessible thanks to the many paths, and for an introduction there are three hiking trails. The forest is part of the Flemish Ecological Network, has been a Flemish nature reserve since 2021 and is protected in Europe as a Natura 2000 area 'Hallerbos and nearby forest complexes with source areas and heaths' (BE2400009) (together with other sub-areas such as the Markvallei, Zuunvallei with the Gaasbeek domain, De Wolfsputten, Kesterbeekvallei, Kesterheide, the Terrijst forest reserve, Lembeekbos, Zevenbronnen, Gasthuisbos, Begijnenbos). Since 2023, the forest has been part of the Brabantse Wouden National Park.